Sam Martingell is the founder of Kombucha Kat, a kombucha producer based in the UK dedicated to brewing organic, craft fermented drinks that look good, taste good and do good.

What inspired you to start selling kombucha?

I founded Kombucha Kat in December 2016 to fulfil a personal dream: to make something good. Years of living in London had left me stressed, depressed and ultimately unwell. My search for a cure somehow led me to the fascinating world of gut health and the microbiome.

I became completely inspired by the idea of the body as a holistic ecosystem and its health as a practice of cultivating all the life within it.

I began making my own fermented foods like kefir, kimchi, sauerkraut and eventually kombucha. When learning how to make kombucha, all the information was from American sources. I realised that the US market was huge but it had yet to really take off in the UK. I felt sure it would though so decided to take a punt.

What are the benefits of kombucha?

Kombucha is a living probiotic drink. It’s made by fermenting sweetened green tea with a special living symbiotic culture of bacteria and yeasts. This culture ‘eats’ the sugar, feeding the creation of more of itself – billions of probiotic bacteria of many strains that are still living in the bottle and fantastic for helping and healing the gut.

More and more scientific research is linking a depleted microbiome to all manner of chronic illness, both physical and mental.

I don’t claim that Kombucha is in itself a cure for anything but consumed as part of a wider practice of maintaining gut health it can help with skin issues, digestion, joint pain and aid the immune system.

Some companies pasteurise their kombucha, why do you not?

Pasteurisation is used to kill off bacteria. This is usually a good thing when we want to prevent products from perishing but the whole point and beauty of kombucha is that it is a living product with living bacteria. Pasteurisation would eliminate most of its beneficial properties.

As our kombucha is unpasteurised and still living in the bottle, this means it is still fermenting the sugars that remain in the tea.

This further fermentation is accelerated by heat and light, so we use amber bottles to prevent this as much as possible in order to maintain the delicate flavour and carbonation of Kombucha Kat.

Why are some of your bottles fizzier than others?

We do not add any carbonation. Instead, Kombucha Kat is naturally carbonated in the bottle as CO2 is a by product of the fermentation process. We cannot control this as no two batches are entirely the same. Our Pomegranate flavoured kombucha is fizzier because the added organic pomegranate juice contains more sugar and therefore more fermentation and more CO2.

How do you ensure the sugar has been digested enough by the scoby?

We test for both sugar levels and acidity throughout the brewing of each batch. This way we can see the sugar drop and acidity rise to the desired levels. Ultimately the true test of each batch is in the taste.

What safety precautions do you take?

Many. Kombucha culture is very sensitive to non organic chemicals so all equipment is regularly steam cleaned. Batches are periodically lab tested for dangerous spores and mold. The accreditations we receive from SALSA and the Soil Association strictly require that all our practices meet the highest safety standards. The cultures grow themselves with every batch. Kombucha Kat is certified both organic by the Soil Association and vegan by the Vegan Society.

How much should a person drink a day?

We recommend that one bottle is enough to begin with. As your body rebalances to accommodate the new bacteria colonies you can then increase your consumption as you wish.